1. Field of the Invention
The present invention relates to an improved method and compositions for imparting flame resistance to wood using dimethyl(oxiranylmethyl)phosphonate (DMOMP) and a catalyst as impregnants. In particular, the present invention relates to impregnating of DMOMP and a catalyst into the wood and reacting the DMOMP with the wood in the presence of the catalyst to chemically bind the DMOMP in situ in the wood.
2. Prior Art
U.S. Pat. No. 2,627,521 to Coover describes the use of oxirane containing phosphonates, including DMOMP, in cellulose derivatives and in polyvinyl resins as plasticizers and stabilizers. There is no suggestion that DMOMP can be used to impregnate the exposed surfaces of wood to impart flame resistance. It is believed that the "cellulose derivatives" referred to by Coover are polymers prepared from cellulose derivatives (e.g. cellulose acetate). Further, no use of catalysts for reacting the DMOMP with wood is described. Coover also describes a process which can be used to prepare DMOMP.
The use of wood for shingles and siding for houses and the like is well known. The problem is to impart some level of flame resistance to these and other wood products such as plywood.